Bit-brace



Patented Aug. 23, |8 98.

No. 6o9,47a.

F. M. STUBGIS.

BIT BRAGE. (Application med Feb. 14, 1398.

(No Model.)-

STATES PATENT rrrong BlT-BRACE.

t SPECIFICATION forming part of Letters Patent No. 609,478; dated August 23, 1898.

Application filed February l l, 1898. Serial No. 670,276. i (Nomodel To all whom zt may concrn: v

`;Be it known that I, FRANCIS M. STURGIS, a citizen of the United States, residing at Shelbyville, in the county of Shelby and State of Illinoisphave invented a new and useful Bit- Brace, of which the following is a specification.

My invention relates to improvements in bit-braces; and the object that I have in view is to provide an improved means which may be operated very quickly to clamp and release the bit and securely hold the latter in place in the head of the tool.

My improvement is designed to overcome the objection to ordinary bit-heads', in which a threaded sleeve is mounted for adjustment longitudinally of the jaws to compress and release the latter, such adjustment of the sleeve requiring a number of turns to properly adjust the jaws; but in my improved brace-head the jaws are compressed or released by giving to the adjustable sleeve a semirotation, thereby effecting a saving in time required to remove one bit and insert another bit.

A further object that I have in View is to provide such a construction of the bit-head in which the adj ustable sleeve is held in place by having it confined against endwise displacement betweenthe bit-head and the jaws; and a further object isto simplify and cheapen the Construction, so as to dispense with pivots for the jaws and toactuate both jaws from a single spring which iscommon to said' jaws;

My invention may be` used in connection with the ordinary brace'or With ratchet-braces and it may readily be applied or attached to either style of such braces to utilize the lat-f ter and save the mechanic the expense of purchasing an entirely new brace to avail himself of the use of my improvement.

With these ends in View the invention con sists in the novel combination of elements and in the Construction and 'arrangement of parts which will be hcreinafterfully described and claimed.

To enable others to understand` the invention, I have illustrated a prcferred embodiment thereof in the accompanying drawings, forming-a part of this specification, and in which- Figure 1 is an elevation of my improved i head applied toa ratchet-brace. Fig. 2 is an enlarged perspective view of the brace-head. Fig. 3 is a longitudinal 'sectional View through the' brace-head on the plane indicated by the dotted line 3 3 of Fig. 4. Fig. 4 is a face or end view of the brace-head. Fig 5 is a transverse section on the plane indicated by the dotted line 5 5 of Fig. 3.

Like numerals of reference denote like and corresponding parts in each of the several figures of the drawings.

My improved head for an ordinary or ratchet brace is designated in its entirety by the numeral 1`, and to this head is united the shank 2 of an ordinary or ratchet brace. It will be understood that the brace proper forms no part of the present invention, which resides ina' novel construction of the head l, adapted to be operated very quickly to clamp and release' any size of bit and effect a saving in the time required to insert or remove the i bit. i

In the drawings I have illustrated the shank 2 as made an integral part of the body of the head 1; but it is obvious that the shank may bemade separate from the head and united thereto in a very secure manncr, such shank being adapted for connection with the brace. The body of the head is integral with a longitudinal spindle 3, arranged centrally in the improved brace-head, and this spindle is of novel Construction to accommodate the extremity of the bit-shank, the clampingjaws, and the pressurespring for said jaws. The' spindle is hollow for a part of its length, and at a suitable point within the open end of the hollow part of the spindle is provided a soeket 5, into which' the eXtremity of the bit-shank may be inserted. The spindle is further provided with longitudinal slots 4, which are formed at diametrically opposite sides of the spindle and which open into the longitudinal opening or bore of the hollow part of said spindle.

The body of the brace-head is provided with an annular collar, which projects from the body and is concentric with the spindle 3. This annular collar 6 isof larger diameter than the spindle, so as to form at the base of the latter an' annular groove 7, which constitutes a seat for the inner end of the axiallyturning adjusting-sleeve, and the exterior IOO 'head to turn freely thereon.

surface of said annular collar G is milled or roughened to prevent the same froni slipping in the hands of the operator.

To accommodate the jaws and the pressurespring therefor, the spindle 3 is provided With the transverse Slots 8 9, and the slot 8 is 'formed through the spindle near the inner extremity of the socket 5, so as to open into the longitudinal slots 4, while the other slot 9 is provided in the spindle below the slot 8 and on a plane within the edge of the annular collar 6.

10 designates the axially-tu rnin g adj ustingsleeve,which is fitted to the body of the brace- The outer end of the adjusting-sleeve is thickened transversely to produce thereon the collar 11, the eXposed surface of which is milled or roughened to provide a secure handhold for the operator when it is desired to rotate the sleeve. The longitudinal bore or passage of this adjusting-sleeve is peculiarly formed to provide the eccentric compressing-faces 12 13, each of which terminates in an abrupt shoulder 14. The compressing-faces 12 13 extend part way around the adjusting-sleeve, and

said faces at the working end of *the sleeve lie eccentric to the aXis thereof. The eccentric faces terminate in the abrupt shoulders 14 and form the notches or spaces 15 at diametrically opposite points in the working end of the sleeve, and these notches are designed to provide for the lateral opening movement of the jaws under the pressure of the spring, so as to permit the jaws to open to their full length and to accommodate bits of large sizes.

The jaws are indicated at 16 17, and they are arranged on opposite sides of the central spindle 3 for movement inwardly toward each other and into the slots 4 under the pressure of the eccentric faces 12 13 of the adjustingsleeve; but to counteract the pressure of said eccentric faces and insure quick opening of said jaws I provide apressure-spring24. In my implement the jaws are not pivotally attached to the body or spindle of the brace-head, but they are loosely confined in place within the lower transverse slot 9 of said spindle. The jaws at their inner ends are formed with the angular heels 18, which are of proper size to fit loosely in the lower transverse slot 9 of said spindle, and said jaws are free to move or play on radial lines with respect to the slotted spindle. The heels of the jaws are inserted into opposite ends of the slot 9, and said jaws are confined between the spindle and the adjusting-sleeve, the parts being so proportioned as to provide for the proper radial movement of the jaws. The free ends of the jaws, which are exposed through the outer working end of the eccentric-formed sleeve, are enlarged to provide the heads 19, and the inner working faces of these heads are grooved, as at 20, and formed with the roughened or serrated gripping-faces 21, thus constructing the heads of the jaws to firmly grip the bit-shank. At the headed ends the jaws are'provided with the outwardly-extending lugs 22, and on the inner sides of said jaws the heads form the abrupt shoulders 23, which serve as seats for the eXtremities of the bent spring 24. This spring is made from a single strip or length of steel bent into the curved or doubled form shown by Fig. 3 of the drawings, the looped or doubled end of the spring being passed through the transverse slot 8 of the spindle, while the arms of said spring are fitted against the shoulders 23 on the inner edges of the movable jaws. The spring is thus confined at one end in the slotted spindle, while the free extremities of said spring engage with the headed jaws, thereby confining the spring against displacement either transversely or longitudinally of the brace-head. The spring tends to move the jaws in opposite directions simultaneously, and said jaws are caused to press .or ride against the eccentric faces of the adj ustingsleeve, whereby when the sleeve is adjusted to have the abrupt shoulders 14 clear the jaws the spring forces said jaws quickly into the notches or spaces 15 of said adjustingsleeve.

One of the important features of my improvement consists in having the ad justingsleeve confined in the brace-head against endwise movement by and between the body and the lugs 22 of the jaws, thereby dispensing with separate fastening means for said adjusting-sleeve. The inner cylindrical end of the adjusting-sleeve is fitted to rotate freely in the annular seat 7 of the body, while the outer end of said sleeve bears against the lugs 22 of the jaws 16 17. It will thus be seen that the sleeve is free to rotate or turn axially on the annular seat and the jaws, and thus the eccentric faces 12 13 of the sleeve are in contact with the jaws to adjust the latter according to the position of the sleeve with relation to said jaws.

The operation may be described, briefiy, as follows: With the eccentric sleeve in the position indicated in Fig. 4 the deep ends of the notches or spaces 15 are opposite to the jaws, and the spring presses the j aws radially and outwardly into said notches, thereby opening the jaws to their full limit. The shank of the bit may now be inserted through the open end of the sleeve and the hollow part of the spindle, so as to rest in the hollow socket 5, and the operator then gives the sleeve a semiturn to cause the eccentric faces 12 13 to ride upon the jaws and force the latter inwardly upon the bit-shank, said sleeve being turned sufficiently to make the jaws grip the bit-shank tightly and hold the bit securely in place in the brace-head. The brace may now be operated in the ordinary way, and the head 1 rotates with the shank of the brace to impart the necessary movement to the bit. To release the bit from the head, it is onlynecessary to reverse the sleeve a sufficient distance to permit the spring to IOO IIO

said sleeve may be given a turning movement snfieient to bring the deep part of the notches 15 opposite to the jaws, thereby enabling the spring to force the ;jaws into the notches free from the bit-shank.

One of the distingnishing features of my invention is the construction ot the sleeve with the eccentric faces and the arrangement of said sleeve with relation to the springpressed jaws, whereby it is only necessary to give a partial turn to the sleeve to compress the jaws or release the same. It is evident that this adjustment may be effected very quickly and that the bit may be inserted or removed in a moments time.

My improvements are very simple, strong, and dnrable in Construction, and while the parts are conpled or united together to prevent displacement thereof and reduce disarrangement to a minimum in the practical service of the implement access is permitted to the spring and the jaws simply by forcing the jaws inwardly into the radial slots of the hollow part of the spindle, thns retracting the lugs 22 of said jaws within the bore of the sleeve, said sleeve being withdrawn from the seat 7 by slipping it endwise over the jaws. The sleeve may be replaced quickly and easily in like manner, and thus either of the jaws or the spring may be replaced in event of injury or breakage.

I am aware that changes in the form and proportion of parts and in the details of c0nstruction may be made by a skilled mechanic without departing from the spirit or sacrificing the advantages of my invention, and I therefore reserve the right to make such ,modifications as clearly fall within the scope of the spindle to embrace the socket-block and having its free ends `engaging with the shoulders, 23, of the jaws, and an external rotatable sleeve seated at its inner end in the recess of the body and engaging at its outer end With the shoulders, 22, of the jaws, said sleeve having the recessed and shcnldered inner faces at opposite sides near the outer end thereof, substantially as described.

In testimony that I claim the foregoing as my own I have hereto affixed my signature in the presence of witnesses.

r. M. STURGIS.

'Witnesses:

B. F. WILsoN, J. N. HUFFER, T. P. RESLER. 

